body {
	font-family: var(--font-sans-serif);
	margin: 0;
	padding: 0;
	color: var(--text-color);
	background-color: #fff;
	line-height: 1.6;
	overflow-x: hidden;
	position: relative;
	/* Prevent horizontal scroll from AOS */
}

html {
	overflow-x: hidden;
	scroll-behavior: smooth;
	/* For smooth scroll to top */
}

.container {
	max-width: 1200px;
	margin: 0 auto;
	width: 90%;
}

/* Header */
header {
	background-color: var(--dark-gray);
	color: white;
	padding: 15px 0;
	position: sticky;
	top: 0;
	width: 100%;
	z-index: 1000;
	box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

header .container {
	display: flex;
	justify-content: space-between;
	align-items: center;
}

.logo {
	font-size: 1.8em;
	font-weight: bold;
	color: #4fc3f7;
	display: flex;
	align-items: center;
	img {
		width: 150px;
		height: 75px;
	}
}

.logo .ai {
	color: #fff;
}

nav#main-nav {
	display: flex;
}

nav#main-nav ul {
	list-style: none;
	margin: 0;
	padding: 0;
	display: flex;
}

nav#main-nav ul li {
	margin-left: 25px;
}

nav#main-nav ul li a {
	color: white;
	text-decoration: none;
	font-size: 20px;
	padding: 0 20px;
	transition: color 0.3s ease;
}

nav#main-nav ul li a:hover,
nav#main-nav ul li a.active {
	color: var(--primary-color);
}

.menu-toggle {
	display: none;
	font-size: 1.8em;
	color: white;
	background: none;
	border: none;
	cursor: pointer;
	padding: 5px;
	z-index: 1002;
}

/* Section Tabs / Main CTAs */
.section-tabs {
	text-align: center;
	padding: 30px 0;
	background-color: var(--light-gray);
	border-bottom: 1px solid var(--border-color);
}

.tab-button {
	background-color: var(--primary-color);
	color: white;
	border: none;
	padding: 12px 25px;
	margin: 0 10px;
	font-size: 1.1em;
	cursor: pointer;
	border-radius: 5px;
	transition:
		background-color 0.3s ease,
		transform 0.2s ease;
	text-decoration: none;
}

.tab-button:hover {
	background-color: #0056b3;
	/* Darker shade of primary */
	transform: translateY(-2px);
}

.tab-button.secondary {
	background-color: var(--secondary-color);
}

.tab-button.secondary:hover {
	background-color: #545b62;
}

/* General Section Styling */
.content-section {
	padding: 90px 0 0 0;
}

.content-section:nth-child(even) {
	/* Alternating background for sections */
	/* background-color: var(--light-gray); */
	/* Optional alternating background */
}

.section-title {
	text-align: center;
	font-size: 2.5em;
	margin-bottom: 20px;
	color: var(--dark-gray);
	position: relative;
}

.section-title::after {
	content: '';
	display: block;
	width: 60px;
	height: 3px;
	background-color: var(--primary-color);
	margin: 10px auto 0;
}

/* Service Item Layout */
.service-item {
	display: flex;
	align-items: center;
	gap: 40px;
	/* Space between image and text */
	margin-bottom: 20px;
}

.service-item:nth-child(even) .service-text {
	order: -1;
	/* Image right, text left for even items */
}

.service-image-placeholder {
	flex: 1 1 45%;
	/* Takes up roughly 45% of the width */
	height: 300px;
	background-color: #e0e0e0;
	display: flex;
	justify-content: center;
	align-items: center;
	color: #757575;
	font-size: 1.2em;
	border-radius: 8px;
	box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.service-text {
	flex: 1 1 55%;
	/* Takes up roughly 55% of the width */
}

.service-text h3 {
	font-size: 1.8em;
	color: var(--primary-color);
	margin-top: 0;
	margin-bottom: 15px;
}

.service-text ul {
	list-style: disc;
	padding-left: 20px;
	margin: 0;
	color: var(--text-muted);
}

.service-text ul li {
	margin-bottom: 8px;
}

.service-text p {
	color: var(--text-muted);
	margin-bottom: 15px;
}

/* Cards layout (for compute power, AI solutions) */
.cards-grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
	gap: 30px;
	margin-top: 20px;
}

.card {
	background-color: var(--card-bg);
	border: 1px solid var(--border-color);
	border-radius: 8px;
	padding: 25px;
	text-align: center;
	box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
	transition:
		transform 0.3s ease,
		box-shadow 0.3s ease;
}

.card:hover {
	transform: translateY(-5px);
	box-shadow: 0 8px 15px rgba(0, 0, 0, 0.1);
}

.card .image-placeholder-small {
	width: 100%;
	height: 150px;
	background-color: #e9ecef;
	margin-bottom: 15px;
	border-radius: 5px;
	display: flex;
	justify-content: center;
	align-items: center;
	color: #6c757d;
}

.card h4 {
	font-size: 1.3em;
	margin-bottom: 10px;
	color: var(--dark-gray);
}

.card p {
	font-size: 0.95em;
	color: var(--text-muted);
}

/* Specific section for "材料卡库" vs. "高精度仿真材料卡" */
.comparison-section {
	display: flex;
	gap: 30px;
	align-items: flex-start;
}

.comparison-item {
	flex: 1;
	border: 1px solid var(--border-color);
	padding: 20px;
	border-radius: 8px;
	background-color: var(--card-bg);
}

.comparison-item h4 {
	text-align: center;
	margin-top: 0;
	color: var(--primary-color);
}

.comparison-image-placeholder {
	width: 100%;
	height: 200px;
	background-color: #e9ecef;
	margin-bottom: 15px;
	border-radius: 5px;
	display: flex;
	justify-content: center;
	align-items: center;
	color: #6c757d;
}

.vs-text {
	align-self: center;
	font-size: 2em;
	font-weight: bold;
	color: var(--primary-color);
	padding: 0 20px;
}

/* AI+数字化解决方案 icons */
.ai-solutions-grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
	gap: 20px;
	text-align: center;
}

.ai-solution-item {
	padding: 15px;
}

.ai-solution-item .icon-placeholder {
	width: 80px;
	height: 80px;
	background-color: #e0f7fa;
	border-radius: 50%;
	margin: 0 auto 10px auto;
	display: flex;
	justify-content: center;
	align-items: center;
	color: var(--primary-color);
	font-size: 1.2em;
	font-weight: bold;
	transition:
		transform 0.3s ease,
		background-color 0.3s ease;
}

.ai-solution-item:hover .icon-placeholder {
	transform: scale(1.1);
	background-color: #b2ebf2;
}

.ai-solution-item p {
	font-size: 0.9em;
	color: var(--text-muted);
}

/* Footer */
footer {
	background-color: var(--dark-gray);
	color: #adb5bd;
	padding: 50px 0 20px 0;
}

.footer-content {
	display: flex;
	flex-wrap: wrap;
	justify-content: space-between;
	gap: 30px;
	margin-bottom: 30px;
}

.footer-column {
	flex: 1;
	min-width: 200px;
	/* Ensure columns don't get too narrow */
}

.footer-column h5 {
	color: white;
	font-size: 1.1em;
	margin-bottom: 15px;
}

.footer-column ul {
	list-style: none;
	padding: 0;
	margin: 0;
}

.footer-column ul li {
	margin-bottom: 8px;
}

.footer-column ul li a {
	color: #adb5bd;
	text-decoration: none;
	transition: color 0.3s ease;
}

.footer-column ul li a:hover {
	color: white;
}

.footer-column p {
	margin-bottom: 8px;
}

.qr-code-placeholder {
	width: 120px;
	height: 120px;
	background-color: #e9ecef;
	display: flex;
	justify-content: center;
	align-items: center;
	margin: 0 auto 10px auto;
	/* Center if column is wide enough */
	color: var(--text-muted);
	font-size: 0.9em;
}

.footer-bottom {
	text-align: center;
	padding-top: 20px;
	border-top: 1px solid #495057;
	font-size: 0.9em;
}

.footer-bottom a {
	color: #adb5bd;
	text-decoration: none;
}

.footer-bottom a:hover {
	color: white;
}

/* Back to Top Button */
.back-to-top {
	position: fixed;
	bottom: 20px;
	right: 20px;
	background-color: var(--primary-color);
	color: white;
	width: 40px;
	height: 40px;
	border-radius: 50%;
	display: flex;
	align-items: center;
	justify-content: center;
	font-size: 1.5em;
	text-decoration: none;
	opacity: 0;
	visibility: hidden;
	transition:
		opacity 0.3s ease,
		visibility 0.3s ease,
		transform 0.3s ease;
	transform: translateY(20px);
	z-index: 990;
	border: none;
	cursor: pointer;

	&.visible {
		opacity: 1;
		visibility: visible;
		transform: translateY(0);
	}

	&:hover {
		background-color: #0056b3;
	}
}

/* Responsive adjustments */
@media (max-width: 992px) {
	/* Tablets and larger phones */
	nav#main-nav ul li {
		margin-left: 15px;
	}

	nav#main-nav ul li a {
		font-size: 0.9em;
	}

	.logo {
		font-size: 1.5em;
	}

	.service-item {
		gap: 20px;
		margin-bottom: 20px;
	}

	.service-text h3 {
		font-size: 1.4em;
	}
}

@media (max-width: 768px) {
	/* Mobile devices */
	.container {
		width: 95%;
	}

	/* Mobile Navigation */
	nav#main-nav {
		display: block;
		position: fixed;
		top: 0;
		left: 0;
		width: 100%;
		height: auto;
		max-height: 100vh;
		overflow-y: auto;
		padding-top: 60px;
		background-color: var(--dark-gray);
		box-shadow: 0 3px 8px rgba(0, 0, 0, 0.25);
		z-index: 999;
		transform: translateY(-100%);
		transition: transform 0.35s ease-in-out;
		visibility: hidden;

		&.nav-active {
			transform: translateY(0%);
			visibility: visible;
		}

		ul {
			flex-direction: column;
			width: 100%;
			padding: 10px 0;
			margin: 0;
		}

		ul li {
			margin: 0;
			width: 100%;
			text-align: center;

			a {
				display: block;
				padding: 12px 20px;
				font-size: 1em;
				color: white;
				border-bottom: 1px solid #495057;
				text-decoration: none;

				&:hover,
				&.active {
					background-color: #495057;
					color: var(--primary-color);
				}
			}

			&:last-child a {
				border-bottom: none;
			}
		}
	}

	.menu-toggle {
		display: block;
	}

	.hero {
		padding: 20px 0;

		h1 {
			font-size: 2em;
		}

		p {
			font-size: 1em;
			padding: 0 10px;
		}
	}

	.section-tabs .container > div {
		flex-direction: column;
		align-items: stretch;
	}

	.tab-button {
		padding: 12px 15px;
		margin: 8px 0;
		font-size: 1.05em;
		display: block;
		width: 100%;
		box-sizing: border-box;
	}

	.section-title {
		font-size: 1.8em;
		margin-bottom: 30px;
	}

	.content-section {
		padding: 0;
	}

	.service-item {
		flex-direction: column;
		gap: 20px;
		margin-bottom: 30px;

		&:nth-child(even) .service-text {
			order: 0;
		}
	}

	.service-image-placeholder,
	.service-text {
		flex: 1 1 100%;
		width: 100%;
	}

	.service-text {
		h3 {
			font-size: 1.3em;
			text-align: center;
		}

		p {
			font-size: 0.9em;
			text-align: center;
		}
	}

	.cards-grid {
		grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
		gap: 20px;
	}

	.card .image-placeholder-small {
		height: 120px;
	}

	.comparison-section {
		flex-direction: column;
		gap: 15px;
	}

	.vs-text {
		transform: rotate(90deg);
		padding: 15px 0;
		align-self: center;
		font-size: 1.5em;
	}

	.comparison-item {
		padding: 15px;
	}

	.comparison-image-placeholder {
		height: 150px;
	}

	.ai-solutions-grid {
		grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
		gap: 15px;
	}

	.ai-solution-item {
		.icon-placeholder {
			width: 60px;
			height: 60px;
			font-size: 0.8em;
		}

		p {
			font-size: 0.8em;
		}
	}

	.solution-features {
		flex-direction: column;
		align-items: center;
	}

	.solution-feature-item {
		margin-bottom: 20px;
		flex-basis: auto;
		width: 80%;
		max-width: 250px;
	}

	footer {
		font-size: 14px;
	}

	.footer-content {
		flex-direction: column;
		align-items: center;
		text-align: center;
		gap: 0;
		margin-bottom: 0;
	}

	.footer-column {
		min-width: 100%;

		&:nth-child(n + 2) {
			ul {
				display: grid;
				grid-template-columns: repeat(3, 1fr);
				gap: 15px;
			}
		}
		&:first-child {
			ul {
				display: grid;
				grid-template-columns: repeat(3, 1fr);
				gap: 15px;
			}
		}
	}

	.qr-code-placeholder {
		margin: 10px auto;
	}

	.footer-bottom {
		font-size: 0.8em;
		padding: 15px 10px;
	}
}

@media (max-width: 480px) {
	.logo {
		font-size: 1.4em;
	}

	.hero {
		h1 {
			font-size: 1.8em;
		}

		p {
			font-size: 0.9em;
		}
	}

	.section-title {
		font-size: 1.6em;
	}

	.service-text {
		h3 {
			font-size: 1.2em;
		}

		p {
			font-size: 14px;
		}
	}

	.card h4 {
		font-size: 1.1em;
	}

	.cards-grid {
		grid-template-columns: 1fr;
	}

	.ai-solutions-grid {
		grid-template-columns: repeat(2, 1fr);
		gap: 10px;
	}

	.ai-solution-item .icon-placeholder {
		width: 50px;
		height: 50px;
	}

	.back-to-top {
		width: 35px;
		height: 35px;
		font-size: 1.3em;
		bottom: 15px;
		right: 15px;
	}
}

.el-carousel__indicators {
	display: flex;
	justify-content: center;
	display: none;
}
.el-carousel__button {
	background-color: rgba(50, 52, 210) !important;
}

.el-carousel__indicators .is-active {
	background-color: rgba(50, 52, 210, 1) !important;
}

.el-carousel__indicators .is-active .el-carousel__button {
	background-color: white !important;
}
